802 research outputs found
On surface plasmon polariton wavepacket dynamics in metal-dielectric heterostructures
The WKB equations for dynamics of the surface plasmon polariton (SPP)
wavepacket are studied. The dispersion law for the SPP in the metal-dielectric
heterostructure with varying thickness of a perforated dielectric layer is
rigorously calculated and investigated using the scattering matrix method. Two
channels of the SPP wavepacket optical losses related to the absorption in a
metal and to the SPP leakage are analyzed. It is shown that change of the
dielectric layer thickness acts on the SPP as an external force leading to
evolution of its quasimomentum and to the wavepacket reversal or even to the
optical Bloch oscillations (BO). Properties of these phenomena are investigated
and discussed. Typical values of the BO amplitude are about tens of microns and
the period is around tens or hundreds of femtoseconds.Comment: 12 pages, 5 figure
Tunable Integrated-Optics Nanoscaled Devices Based on Magnetic Photonic Crystals
Magnetooptical properties of magnetic photonic crystals have been
investigated in the view of their possible applications for the modern
integrated-optics devices. A "transfer matrices" formalism was expanded for the
case of oblique light incidence on the periodic nanoscaled magnetic
multilayered systems. Several new effects such as the Faraday effect dependence
on the incidence angle and the tunability of the bandgap defect modes spectral
location by external magnetic fields were found. Several possibilities of
one-dimensional magnetic photonic crystals applications for the optical devices
are discussed. Initial steps towards the practical implementation of the
proposed devices are reported.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Inverse Transverse Magneto-Optical Kerr Effect
It is demonstrated that a static in-plane magnetic field is generated in a
ferromagnetic film by p-polarised light obliquely incident on the film. This
phenomenon can be called inverse transverse magneto-optical Kerr effect. The
femtosecond laser pulse of peak intensity of 500 W/{\mu}m2 generates in nickel
an effective magnetic field of about 100 Oe. The value of the effective
magnetic field can be increased by more than an order of magnitude at the
surface plasmon polariton resonance excited in smooth metal dielectric
structures or in plasmonic crystals.Comment: 4 pages, 3 figure
Plasmonic crystals for ultrafast nanophotonics: Optical switching of surface plasmon polaritons
We demonstrate that the dispersion of surface plasmon polaritons in a
periodically perforated gold film can be efficiently manipulated by femtosecond
laser pulses with the wavelengths far from the intrinsic resonances of gold.
Using a time- and frequency- resolved pump-probe technique we observe shifting
of the plasmon polariton resonances with response times from 200 to 800 fs
depending on the probe photon energy, through which we obtain comprehensive
insight into the electron dynamics in gold. We show that Wood anomalies in the
optical spectra provide pronounced resonances in differential transmission and
reflection with magnitudes up to 3% for moderate pump fluences of 0.5 mJ/cm^2.Comment: 5 pages, 4 figure
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